Staple chamber assembly and linear surgical stitching device using said staple chamber assembly

ABSTRACT

A linear surgical stapler includes an upper staple cartridge receiving half-section, a lower staple cartridge receiving half-section and a staple cartridge assembly. The staple cartridge assembly includes a cutting groove in which a reciprocating movement cutter is mounted. The cutter includes a bottom surface and a knife blade located at a far end of the cutter. The staple cartridge assembly includes a restricting member mounted therein and an elastic stopper. The elastic stopper abuts against the restricting member when the staple cartridge assembly is in an initial state. The restricting member breaks away from the staple cartridge assembly when the staple cartridge assembly is in a firing complete state, thereby preventing the cutter from sliding towards the far end of the staple cartridge. As a result, misfiring throughout the whole operation of the linear surgical stapler is prevented.

This application claims the benefit of priority to Chinese PatentApplication No. 201010581554.7 titled “A KIND OF LINEAR SURGICALSTAPLER”, filed with the Chinese State Intellectual Property Office onDec. 10, 2010, the entire disclosure of which is incorporated herein byreference.

FIELD OF THE INVENTION

The present invention relates to a staple cartridge assembly and alinear surgical stapler having such staple cartridge assembly, whichbelongs to the technical fields of medical devices.

BACKGROUND OF THE INVENTION

Surgical stitching instruments have been widely used in surgicaloperations for stitching up wounds, and stitching up and cuttinginterior tissues. U.S. Pat. No. 5,129,570 discloses a typical surgicalstitching instrument which is provided with double functions ofstitching and cutting. That is to say, the surgical stitching instrumentis capable of stitching up wounds and simultaneously cutting spilthtissues. Such surgical stitching instruments usually include a pair oftop and bottom forceps, a closing handle for closing the top and bottomforceps, an anvil and a staple cartridge respectively mounted onopposite far ends of the top and bottom forceps, a staple-pushing rod, astaple-pushing piece and a cutter all moveably mounted in the staplecartridge, and a push button for moveably pushing the staple-pushingpiece and the cutter. The staple cartridge includes inside stitch nailswhich are pushed by the staple-pushing piece to move towards the anvil.The tissues between the staple cartridge and the anvil are cut off bythe cutter.

Error firing action means that after the instrument has been fired, itrefires without any nails in the reloading unit. The consequence of sucherror firing action will extrude the nails which have already wellclosed and will cause over-deformation of the nails. As a result, thewound closure cannot be good enough, and serious medical malpracticesand sequelae sometimes occur.

In order to avoid this kind of phenomenon, the conventional surgicalstitching instruments usually have safety mechanisms for error firingprotection.

U.S. Pat. No. 5,129,570 discloses such a safety mechanism which includesa middle safety block having a cutter channel and a staple-pushing rodchannel, and an elastic piece mounted below the cutter. When theinstrument is at an open position, which means the top and bottomforceps are not closed, the cutter are upsprung by the elastic piece sothat the cutter cannot pass the cutter channel. When the instrument isloaded with the staple cartridge, a transverse lever which is pivotallymounted on top of the staple cartridge presses against a top portion ofthe cutter. The cutter overcomes the elasticity of the elastic piece andrecovers to a position where the cutter can pass through the cutterchannel. As a result, under this condition, the instrument can be usedin firing. When the instrument is completely fired, the cutter is pulledback to the original position. Under this condition, the transverselever has been pivoted to a position where the transverse lever cannotpress the top portion of the cutter anymore. The cutter is upsprungagain by the elastic piece so that the cutter cannot pass the cutterchannel and thereby preventing error firing.

U.S. Pat. No. 7,055,730 discloses another safety mechanism whichincludes a protection cover mounted on the cutter. The protection coveris connected to the staple cartridge through a pin and the protectioncover is rotatable with respect to the pin under the function of atorsional spring. The protection cover is mateable with and connected tothe cutter before firing of the instrument for not only protecting theblade, but also keeping horizon for closing the instrument. When theinstrument is completely fired, the cutter returns back to the originalposition. Under this condition, the protection cover breaks away fromthe cutter, once the instrument is opened, the protection coveroverturns immediately under the function of the torsional spring. Theprotection cover is ultimately and vertically located between the anviland the staple cartridge which results in the instrument unclosed,thereby avoiding the error firing possibility of the instrument.However, in fact, such safety mechanism cannot absolutely avoid emptyfiring of the instrument between the time after the firing of theinstrument is complete and before the instrument is opened. Therefore,the conventional second error firing protection cannot continue theentire process between the time when the firing of the instrument iscomplete and before a new staple cartridge is installed. Thus, certainoperation risk still exists.

BRIEF SUMMARY OF THE INVENTION

An object of the present application is to provide a staple cartridgeassembly with simple structure for preventing error firing, and a linearsurgical stapler having such staple cartridge assembly.

In order to solve the above technical problems, it is provided accordingto an illustrated embodiment of the present application a staplecartridge assembly including a cutting groove in which a reciprocatingmovement cutter is mounted. The cutter includes a bottom surface and aknife blade located at a far end of the cutter. The staple cartridgeassembly includes a restricting member mounted therein and an elasticstopper for mating with the restricting member. The restricting memberand the elastic stopper define a first position and a second position.The elastic stopper abuts against the restricting member when theelastic stopper is located at the first position. The restricting member(4) breaks away from the staple cartridge assembly when the elasticstopper is located at the second position.

Preferably, the elastic stopper includes a moveable button and a springresisting against a bottom portion of the moveable button.

Preferably, the staple cartridge assembly includes a through hole inwhich the moveable button and the spring are accommodated. An axis ofthe through hole is perpendicular to and in communication with a centralline of the cutting groove. A top portion of the moveable button isextendable beyond the through hole under the function of the spring.

Preferably, the staple cartridge assembly includes a cushion block, thecushion block being fixed to the staple cartridge assembly, and anotherend of the spring resisting against a top surface of the cushion block.

Preferably, the through hole includes a step and the moveable buttonincludes an embossment under condition that an external diameter of theembossment is larger than an internal diameter of the step.

Preferably, the top portion of the moveable button is of a wedgeconfiguration.

Preferably, the elastic stopper includes a rotatable block and a torsionspring acting on the rotatable block.

Preferably, the rotatable block includes a limiting surface forrestricting movement of a cutter-pushing rod when the staple cartridgeassembly is in a firing state.

Preferably, a minimum distance between the limiting surface and arotating axis of the rotatable block is larger than a perpendiculardistance between the bottom surface and the rotating axis of therotatable block.

Preferably, the elastic stopper is structured as an elastic metal piece,one end of which is fixedly connected to a bottom portion of the staplecartridge assembly.

In order to solve the above technical problems, it is also providedaccording to an illustrated embodiment of the present application alinear surgical stapler comprising an upper staple cartridge receivinghalf-section, a lower staple cartridge receiving half-section and astaple cartridge assembly for supporting the lower staple cartridgereceiving half-section. The staple cartridge assembly includes a cuttinggroove in which a reciprocating movement cutter is mounted. The cutterincludes a bottom surface and a knife blade located at a far end of thecutter. The staple cartridge assembly comprises a restricting membermounted therein and an elastic stopper for mating with the restrictingmember. The restricting member and the elastic stopper define a firstposition and a second position. The elastic stopper abuts against therestricting member when the elastic stopper is located at the firstposition. The restricting member (4) breaks away from the staplecartridge assembly when the elastic stopper is located at the secondposition.

Preferably, the elastic stopper includes a moveable button and a springresisting against a bottom portion of the moveable button.

Preferably, the staple cartridge assembly includes a through hole inwhich the moveable button and the spring are accommodated. An axis ofthe through hole is perpendicular to and in communication with a centralline of the cutting groove. A top portion of the moveable button isextendable beyond the through hole under the function of the spring.

Preferably, the staple cartridge assembly includes a cushion block, thecushion block being fixed to the staple cartridge assembly, and anotherend of the spring resisting against a top surface of the cushion block.

Preferably, the through hole includes a step and the moveable buttonincludes an embossment under condition that an external diameter of theembossment is larger than an internal diameter of the step.

Preferably, the top portion of the moveable button is of a wedgeconfiguration.

Preferably, the elastic stopper includes a rotatable block and a torsionspring acting on the rotatable block.

Preferably, the rotatable block includes a limiting surface forrestricting movement of a cutter-pushing rod when the staple cartridgeassembly is in a firing state.

Preferably, a minimum distance between the limiting surface and arotating axis of the rotatable block is larger than a perpendiculardistance between the bottom surface and the rotating axis of therotatable block.

Preferably, the elastic stopper is structured as an elastic metal piece,one end of which is fixedly connected to a bottom portion of the staplecartridge assembly.

In order to solve the above technical problems, it is also providedaccording to an illustrated embodiment of the present application astaple cartridge assembly comprising a cutting groove in which areciprocating movement cutter is mounted. The cutter includes a bottomsurface and a knife blade located at a far end of the cutter. The staplecartridge assembly comprises a restricting member mounted therein, anelastic stopper and a receiving cavity located at a far-end bottomsection of the staple cartridge assembly for receiving the restrictingmember. The staple cartridge assembly defines an initial state and afiring state. The restricting member is located on top of the elasticstopper and prevents a top end of the elastic stopper from protrudingbeyond the bottom surface when the staple cartridge assembly is in theinitial state. The restricting member is remained in the receivingcavity in order that the top end of the elastic stopper engages with thecutter to thereby preventing reciprocating movement of the cutter whenthe firing state of the staple cartridge assembly is completed.

Preferably, the elastic stopper comprises a moveable button and a springresisting against a bottom portion of the moveable button. Therestricting member is located on top of the moveable button when therestricting member is in the initial state.

Preferably, the staple cartridge assembly further includes a throughhole in which the moveable button and the spring are accommodated. Anaxis of the through hole is perpendicular to and in communication with acentral line of the cutting groove. A top portion of the moveable buttonis extendable beyond the through hole under the function of the spring.

Preferably, the staple cartridge assembly further includes a cushionblock, the cushion block being fixed to the staple cartridge assembly,and another end of the spring resisting against a top surface of thecushion block.

Preferably, the through hole comprises a step and the moveable buttoncomprises an embossment under condition that an external diameter of theembossment is larger than an internal diameter of the step.

Preferably, the top portion of the moveable button is of a wedgeconfiguration.

Preferably, the elastic stopper comprises a rotatable block and atorsion spring acting on the rotatable block. The restricting member islocated on top of the rotatable block when the restricting member is inthe initial state.

Preferably, the rotatable block comprises a limiting surface forrestricting movement of a cutter-pushing rod when the staple cartridgeassembly is in the firing state.

Preferably, a minimum distance between the limiting surface and arotating axis of the rotatable block is larger than a perpendiculardistance between the bottom surface and the rotating axis of therotatable block.

Preferably, the elastic stopper is structured as an elastic metal pieceunder condition that one end of the elastic metal piece is fixedlyconnected to a bottom portion of the staple cartridge assembly, and theother end of the elastic metal piece engages against a bottom portion ofthe restricting member when the staple cartridge assembly is in theinitial state and restricts movement of a cutter-pushing rod when thestaple cartridge assembly is in the firing state.

In order to solve the above technical problems, it is also providedaccording to an illustrated embodiment of the present application alinear surgical stapler comprising an upper staple cartridge receivinghalf-section, a lower staple cartridge receiving half-section and astaple cartridge assembly for supporting the lower staple cartridgereceiving half-section. The staple cartridge assembly comprises acutting groove in which a reciprocating movement cutter is mounted. Thecutter includes a bottom surface and a knife blade located at a far endof the cutter. The staple cartridge assembly comprises a restrictingmember mounted therein, an elastic stopper and a receiving cavitylocated at a far-end bottom section of the staple cartridge assembly forreceiving the restricting member. The staple cartridge assembly definesan initial state and a firing state. The restricting member is locatedon top of the elastic stopper and prevents a top end of the elasticstopper from protruding beyond the bottom surface when the staplecartridge assembly is in the initial state. The restricting member isremained in the receiving cavity in order that the top end of theelastic stopper engages with the cutter to thereby preventingreciprocating movement of the cutter when the firing state of the staplecartridge assembly is completed.

Preferably, the elastic stopper comprises a moveable button and a springresisting against a bottom portion of the moveable button. Therestricting member is located on top of the moveable button when therestricting member is in the initial state.

Preferably, the staple cartridge assembly further includes a throughhole in which the moveable button and the spring are accommodated. Anaxis of the through hole is perpendicular to and in communication with acentral line of the cutting groove. A top portion of the moveable buttonis extendable beyond the through hole under the function of the spring.

Preferably, the staple cartridge assembly further includes a cushionblock, the cushion block being fixed to the staple cartridge assembly,and another end of the spring resisting against a top surface of thecushion block.

Preferably, the through hole comprises a step and the moveable buttoncomprises an embossment under condition that an external diameter of theembossment is larger than an internal diameter of the step.

Preferably, the top portion of the moveable button is of a wedgeconfiguration.

Preferably, the elastic stopper comprises a rotatable block and atorsion spring acting on the rotatable block. The restricting member islocated on top of the rotatable block when the restricting member is inthe initial state.

Preferably, the rotatable block comprises a limiting surface forrestricting movement of a cutter-pushing rod when the staple cartridgeassembly is in the firing state.

Preferably, a minimum distance between the limiting surface and arotating axis of the rotatable block is larger than a perpendiculardistance between the bottom surface and the rotating axis of therotatable block.

Preferably, the elastic stopper is structured as an elastic metal pieceunder condition that one end of the elastic metal piece is fixedlyconnected to a bottom portion of the staple cartridge assembly, and theother end of the elastic metal piece engages against a bottom portion ofthe restricting member when the staple cartridge assembly is in theinitial state and restricts movement of a cutter-pushing rod when thestaple cartridge assembly is in the firing state.

Compared to the prior arts, the present application provides theadvantage of simple structure, and prevents misfiring throughout thewhole operation from the completion of a firing to the exchange of a newstaple cartridge, thereby eliminating the possibility of misfiring aftera first firing and providing more safety.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a structural schematic view of a staple cartridge assembly inaccordance with a first illustrated embodiment of the presentapplication;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;

FIG. 3 is an enlarged view of portion B of FIG. 1;

FIG. 4 is an exploded schematic view of the staple cartridge assembly inaccordance with the first illustrated embodiment of the presentapplication;

FIG. 5 is a structural schematic view of a staple cartridge assembly inaccordance with a second illustrated embodiment of the presentapplication when the staple cartridge assembly is in an initial state;and

FIG. 6 is a structural schematic view of the staple cartridge assemblyin accordance with the second illustrated embodiment of the presentapplication when the staple cartridge assembly is in a firing state.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present application discloses a linear surgical stapler, especiallya staple cartridge assembly. As shown in FIGS. 1 to 4, the same as priorarts, the present application according to a first embodiment includes astaple cartridge 1 and a knife base 2 fixed with each other. The staplecartridge 1 includes a cutting groove in which a cutter 8 is mounted.The cutter 8 is movable back and forth along the axis of the cuttinggroove. The cutter 8 includes a bottom surface 10 and a knife blade 11.Certainly, the staple cartridge 1 therein further includes a positioninghole, a staple-pushing piece and a nail disposed inside the positioninghole etc. Since such structures are irrelated to the presentapplication, detailed description thereabout is omitted herein.

First Embodiment

The staple cartridge 1 includes a through hole 3 located adjacent to anear-end bottom side of the staple cartridge 1. The through hole 3 is incommunication with the cutting groove. According to the presentapplication, a front-to-back direction means a left-to-right directionof the drawings, and a top-to-bottom direction means a top-to-bottomdirection of the drawings. In a preferred embodiment, the through hole 3is associated therein a moveable button 5 which is capable ofreciprocating movement along an axis of the through hole. The bottomside of the moveable button 5 is provided with a spring 6. One end ofthe spring 6 abuts against the moveable button 5 so that the moveablebutton 5 always suffers a pushing force which directly tends towards thebottom surface 10. The bottom side of the spring 6 is provided with acushion block 7 which is securely fixed to the bottom face of the staplecartridge 1. The other end of the spring 6 resists against a top surfaceof the cushion block 7. In this wise, the moveable button 5 is alwaysdriven by the spring 6 to move towards the cutter 8.

Certainly, the cushion block 7 can be omitted and let the other end ofthe spring 6 directly resisting on the knife base 2. Referring to FIG.3, the through hole 3 includes a step 12 and the moveable button 5includes an embossment 13 for mating with the step 12. An externaldiameter of the embossment 13 is larger than an internal diameter of thestep 12 as a result that even if the force of the spring 6 is alwaysapplied to the moveable button 5, the moveable button 5 can be preventedfrom withdrawing the through hole 3. Furthermore, referring to thedrawings, a top portion of the moveable button 5 is of a wedgeconfiguration. The top portion of the moveable button 5 is extendablebeyond the through hole 3 under the function of the spring 6. In thecurrent embodiment, the moveable button 5 and the spring 6 together forman elastic stopper 30.

The staple cartridge assembly according to the present applicationdefines two states including an initial state and a firing completestate. When the staple cartridge assembly is in the initial state, asliding block 4 is provided on top of the through hole 3 and forward thecutter 8. The sliding block 4 is a kind of restricting member. Thesliding block 4 is located on top of the moveable button 5 and generatesa relative acting force applied to the moveable button 5. The slidingblock 4 can be of any shapes and the illustrated rectangular shape isonly for demonstration. In the present application, as long as thesliding block 4 capable of sliding from a near-end of the staplecartridge to a far-end of the staple cartridge is okay. The knife base 2includes a recess 9 at the far-end thereof. Both the width and theheight are larger than or equal to those of the sliding block 4. Themaximum distance between the recess 9 and the through hole 3 is smallerthan or equal to a movable distance of the cutter 8. As a result, it isinsure that when the sliding block 4 slides from the near-end to thefar-end of the staple cartridge, it can be dropped out into the recess9. In order to make the sliding block 4 falls into the recess 9 mucheasier, front and rear sides of the sliding block can be designed withslope surfaces. Alternatively, the receiving cavity for receiving thesliding block can be arranged at the farthest bottom portion of thestaple cartridge or the farthest portion of the cutter, thereby thereceiving cavity can be a vacant area rather than the recess. The vacantarea is located at the farthest staple cartridge and cannot be reachedby the cutter.

The following working process of the preferred embodiment will bedescribed in simple.

When the staple cartridge assembly is in the initial state, the moveablebutton 5, the spring 6 and the cushion block 7 are assembled in thethrough hole 3 of the staple cartridge in turn. The sliding block 4 issandwiched between the moveable button 5 and the bottom surface 10 withthe sliding block 4 pressing against the moveable button 5. When thestaple cartridge is in the firing process, the sliding block 4 is pushedto move forwardly by the cutter 8. During sliding, the sliding block 4will fall into the predetermined recess 9 to prevent the sliding block 4from returning back to the initial position. In such process, themoveable button 5 always resists against the bottom surface 10 of thecutter 8. When the staple cartridge assembly is in the firing completestate, the cutter 8 is pulled back to the initial position where themoveable button 5 breaks away from the sliding block 4. Under thiscondition, without the oppression of the slider block 4, the moveablebutton 5 is upsprung by the spring 6 and is fixed to the far-end of theknife blade 11. As a result, the cutter 8 is restricted by the moveablebutton 5 to prevent the cutter 8 from moving forwardly. The instrumentof the present application can be prevented from second error refiringand thereby realizing the purpose of the present application.

Second Embodiment

Referring to FIGS. 5 and 6, according to the current embodiment, theelastic stopper 32 includes a rotatable block 14 pivotally mounted inthe staple cartridge and a torsion spring 15 acting on the rotatableblock 14. The torsion spring 15 always applies an acting force fordriving the rotatable block 14 rotating clockwise. The rotatable block14 includes a limiting surface 16 for restricting movement of acutter-pushing rod when the staple cartridge assembly is in the firingstate. The sliding block 4 is located on top of the rotatable block 14in the initial state.

When the staple cartridge assembly is in the initial state as shown inFIG. 5, the sliding block 4 presses against the rotatable block 14. Whenthe staple cartridge is in the firing process, the sliding block 4 ispushed to move forwardly by the cutter 8. During sliding, the slidingblock 4 will fall into the predetermined recess 9 to prevent the slidingblock 4 from returning back to the initial position. In such process,the moveable button 5 always resists against the bottom surface 10 ofthe cutter 8. When the staple cartridge assembly is in the firingcomplete state, as shown in FIG. 6, the cutter 8 is pulled back to theinitial position where the moveable button 5 breaks away from thesliding block 4. Under this condition, without the oppression of theslider block 4, the rotatable block 14 rotates clockwise by the torsionspring 15. In this embodiment, a minimum distance between the limitingsurface 16 and a rotating axis of the rotatable block 14 is larger thana perpendicular distance between the bottom surface 10 and the rotatingaxis of the rotatable block 14. As a result, it is insure that when therotatable block 14 rotates to the state as shown in FIG. 6, the limitingsurface 16 can be fixed to the far-end of the knife blade 11. Thereby,the cutter 8 is restricted by the rotatable block 14 to prevent thecutter 8 from moving forwardly. The instrument of the presentapplication can be prevented from second error refiring and therebyrealizing the purpose of the present application.

The far-end of the present application is an end far from an operatorand the near-end is an end near the operator. The present applicationmay have multiple embodiments, for example, the elastic stopper includesan elastic metal piece with one end fixedly connected to a bottomportion of the staple cartridge assembly, and the other end abuttingagainst the bottom portion of the sliding block 4 when the staplecartridge assembly is in the initial state. When the staple cartridgeassembly is in the firing state, since the sliding block is received inthe recess 9, the other end of the elastic metal piece protrudes acertain distance. The elastic metal piece can be fixed to the far-end ofthe knife blade 11. Thereby, the cutter 8 is restricted by the rotatableblock 14 to restrict movement of the cutter-pushing rod. It should benoted that, those skilled in the art may make many improvements andmodifications to the present application without departing from theprinciple of the present application, and these improvements andmodifications also fall into the protection scope of the claims of thepresent application.

What is claimed is:
 1. A staple cartridge assembly, comprising: areciprocating movement cutter which is moveable along a longitudinaldirection, the cutter comprising a bottom surface and a knife bladelocated at a far end of the cutter; a sliding block which is slideablein the longitudinal direction; a stopper is configured to press againstthe sliding block first and then press against the bottom surface of thecutter in the process of the cutter moves forward in the longitudinaldirection together with the sliding block; and a receiving spacepositioned at a far end of the staple cartridge assembly; wherein thereceiving space comprises a recess and the sliding block falls into therecess under the forward moving of the cutter in the longitudinaldirection, and the cutter is pulled backward in the longitudinaldirection to a initial position where the stopper extends beyond thebottom surface of the cutter in order that the cutter is prevented fromfurther moving forward along the longitudinal direction.
 2. The staplecartridge assembly as claimed in claim 1, wherein the recess has a widthand a height that are larger than or equal to those of the slidingblock.
 3. The staple cartridge assembly as claimed in claim 1, wherein amaximum distance between the recess and the stopper is smaller than orequal to a movable distance of the cutter.
 4. The staple cartridgeassembly as claimed in claim 1, wherein the stopper comprises a moveablebutton and a spring resisting against a bottom portion of the moveablebutton; the staple cartridge assembly comprises a through hole in whichthe moveable button and the spring are accommodated, an axis of thethrough hole being perpendicular to the longitudinal direction, a topportion of the moveable button being extendable beyond the through holeunder the function of the spring.
 5. The staple cartridge assembly asclaimed in claim 4, comprising a cushion block, the cushion block beingfixed to the staple cartridge assembly, one end of the spring resistingagainst the moveable button, and the other end of the spring resistingagainst a top surface of the cushion block.
 6. The staple cartridgeassembly as claimed in claim 4, wherein the through hole comprises astep and the moveable button comprises an embossment under conditionthat an external diameter of the embossment is larger than an internaldiameter of the step.
 7. The staple cartridge assembly as claimed inclaim 4, wherein the top portion of the moveable button is of a wedgeconfiguration.
 8. The staple cartridge assembly as claimed in claim 1,wherein the stopper comprises a rotatable block pivotally mounted in thestaple cartridge assembly and a torsion spring acting on the rotatableblock, the rotatable block comprising a limiting surface to restrictforward movement of the cutter at the initial position, the slidingblock being located on top of the rotatable block and being pressedagainst by the rotatable block.
 9. The staple cartridge assembly asclaimed in claim 8, wherein a minimum distance between the limitingsurface and a rotating axis of the rotatable block is larger than aperpendicular distance between the bottom surface of the cutter and therotating axis of the rotatable block.
 10. The staple cartridge assemblyas claimed in claim 1, wherein the stopper comprises an elastic metalpiece with one end fixedly connected to a bottom portion of the staplecartridge assembly, and another end abutting against a bottom portion ofthe sliding block; the another end extends beyond the bottom surface ofthe cutter at the initial position in order to restrict further forwardmovement of the cutter.
 11. A linear surgical stapler, comprising: astaple cartridge receiving section; and a staple cartridge assembly,including: a reciprocating movement cutter which is moveable along alongitudinal direction, the cutter comprising a bottom surface and aknife blade located at a far end of the cutter; a sliding block which isslideable in the longitudinal direction; a stopper configured to pressagainst the sliding block first and then press against the bottomsurface of the cutter in the process of the cutter moving forward in thelongitudinal direction together with the sliding block; and a receivingspace positioned at a far end of the staple cartridge assembly; whereinthe receiving space comprises a recess and the sliding block falls intothe recess under the forward moving of the cutter in the longitudinaldirection, and the cutter is pulled backward in the longitudinaldirection to an initial position where the stopper extends beyond thebottom surface of the cutter in order that the cutter is prevented fromfurther moving forward along the longitudinal direction.
 12. The linearsurgical stapler as claimed in claim 11, wherein the recess has a widthand a height that are larger than or equal to a width and a height ofthe sliding block.
 13. The linear surgical stapler as claimed in claim11, wherein a maximum distance between the recess and the stopper issmaller than or equal to a movable distance of the cutter.
 14. Thelinear surgical stapler as claimed in claim 11, wherein the stoppercomprises a moveable button and a spring resisting against a bottomportion of the moveable button; the staple cartridge assembly comprisesa through hole in which the moveable button and the spring areaccommodated, an axis of the through hole being perpendicular to thelongitudinal direction, a top portion of the moveable button beingextendable beyond the through hole under the function of the spring. 15.The linear surgical stapler as claimed in claim 14, comprising a cushionblock, the cushion block being fixed to the staple cartridge assembly,one end of the spring resisting against the moveable button, and theother end of the spring resisting against a top surface of the cushionblock.
 16. The linear surgical stapler as claimed in claim 14, whereinthe through hole comprises a step and the moveable button comprises anembossment under condition that an external diameter of the embossmentis larger than an internal diameter of the step.
 17. The linear surgicalstapler as claimed in claim 14, wherein the top portion of the moveablebutton is of a wedge configuration.
 18. The linear surgical stapler asclaimed in claim 11, wherein the stopper comprises a rotatable blockpivotally mounted in the staple cartridge assembly and a torsion springacting on the rotatable block, the rotatable block comprising a limitingsurface to restrict forward movement of the cutter at the initialposition, the sliding block being located on top of the rotatable blockand being pressed against by the rotatable block.
 19. The linearsurgical stapler as claimed in claim 18, wherein a minimum distancebetween the limiting surface and a rotating axis of the rotatable blockis larger than a perpendicular distance between the bottom surface ofthe cutter and the rotating axis of the rotatable block.
 20. The linearsurgical stapler as claimed in claim 11, wherein the stopper comprisesan elastic metal piece with one end fixedly connected to a bottomportion of the staple cartridge assembly, and another end abuttingagainst a bottom portion of the sliding block; the another end extendsbeyond the bottom surface of the cutter at the initial position in orderto restrict further forward movement of the cutter.